Quoting from developer’s site:

Already upgraded to Mac OS X Lion? Yes? Well then you certainly know Launchpad, the “home for your apps” like Apple says.

A huge disadvantage of Launchpad is that every app located in your /Applications folder is shown. That means that you will see little helper programs like uninstallers or updaters, too.
These apps can’t be hidden from Launchpad easily because Apple does not provide any preference pane or tool to do so.

Launchpad-Control is a small tool which allows you to easily hide/unhide apps (and groups) from Launchpad in Mac OS X Lion.

NOTE: it is free, but be kind and make a donation to the developer, he will appreciate it very much. 😉